The present invention relates generally to optical switches and switch mirror arrays. More particularly, the present invention relates to micro-electro-mechanical-system (MEMS) switch mirror arrays. Specifically, the present invention relates to an optical switch having switch mirror arrays controlled by scanning beams.
An optical switch is a switching device that couples light beams from an input fiber to an output fiber. Typically, the light beams from an input fiber are collimated and directed toward a desired location such as an output fiber. A movable mirror (e.g., a gimbaled mirror) in a switch mirror array redirects light beams to desired locations. A common way of moving the mirror is by electrostatic actuation using electrodes, which are positioned below the mirror. A voltage is applied to the electrodes that creates an electric field, which causes the mirror to pivot. To address and control each individual mirror in a switch mirror array, a large number of electrical connections is required to provide voltage to the electrodes.
Thus, a limitation with constructing large optical switches with a large number of mirrors is the amount of electrical connections needed to address and drive each mirror. Typically, a mirror requires four electrostatic electrodes to move the mirror in different directions from its equilibrium position. As such, a controller or driver must be electrically connected to each electrode. Consequently, to have a large number of mirrors for an optical switch, a large amount of space is required to accommodate for the number of electrical connections needed for the electrodes. Therefore, constructing a large optical switch with a large number of mirrors becomes complex due to the amount of electrical connections needed.
An optical switch having switch mirror arrays controlled by scanning beams is disclosed. Movement of individual mirrors in switch mirror arrays is controlled by one or more scanning beams. The optical switch includes one or more arrays of optical switch inputs and outputs and one or more arrays of movable mirrors to direct light beams from the optical switch inputs to the optical switch outputs. The optical switch also includes one or more control elements to control the movable mirrors based on scanning beams directed to the one or more control elements.